Jokes aside, I do believe it’s a good idea - at least it will stand out in this age of AI outreach. I would add something to the postcard though - something small but physical. Here's an inspiring story: our CEO’s mom is into knitting. So he asked her to knit a bunch of cute piggies with our company logo on them. Our ceo would then take those piggies to conferences and gift them to people he spoke with - always telling that is was handcrafted by his mom.
People loved this - see photo